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1.
首次合成一系列杯[10]冠醚。通过将对叔丁基杯[10]芳烃和乙二醇双对甲苯磺酸酯或多甘醇双对甲苯磺酸酯在K2CO3/甲苯或Cs2CO3/丙酮体系中反应,得到一系列杯[10]冠醚:1,2-杯[10]冠-4、1,3-杯[10]冠-2、1,2-,1,3-杯[10]冠-3、1,4-杯[10]冠-4、和1,6-杯[10]冠-4。  相似文献   

2.
Five novel Schiff's bases p‐tert‐butylcalix[4]arenes have been synthesized in high yields by the reaction of 1,3‐distally disubstituted p‐tert‐butylcalix[4]arene amine (1) with the corresponding aromatic aldehydes, and their cation binding abilities and selectivities with alkali and heavy metal ions have been evaluated by solvent extraction of aqueous metal picrates to show the highest Ag+ extractability for Schiff's base p‐tert‐butylcalix[4]arene (6) and the best Na+/Li+ and Ag+/Ti+ selectivities for Schiff's base p‐tert‐butylcalix[4]arene (4 and 2) over any other calix[4]arene derivatives, respectively.  相似文献   

3.
25, 25′, 27, 27′‐Bis(1,3‐dioxypropane)‐bis(5, 11, 17, 23‐tetra‐tert‐butylcalix[4]arene‐26,28‐diol) (4) and 25, 25′, 27, 27′‐bis(1, 4‐dioxybutane)‐bis (5, 11, 17, 23‐tetra‐tert‐butylcalix‐[4]arene‐26, 28‐diol) (5) were synthesized by the reaction of p‐tert‐butylcalix[4]arene (1) with preorganized 25, 27‐bis(3‐bromoproxyl)calix[4]arene‐26, 27‐diol (2) and 25, 27‐bis(3‐bromobutoxyl)calix[4]arene‐26, 27‐diol (3) in the presence of K2CO3 and KI. Compounds 4 and 5 were characterized with X‐ray analysis and the selectivity of 4 and 5 toward K+ over other alkali metal ions, alkaline metal ions as well as NH4+ were investigated with an ion‐selective electrode.  相似文献   

4.
New photoreactive calixarene derivatives containing spiro ortho ester groups (calixarenes 3a–3c ) were synthesized by the reaction of 2‐bromomethyl‐1,4,6‐trioxaspiro[4.4]nonane with 2,8,14,20‐tetramethyl‐4,6,10,12,16,18,22,24‐octakis(carboxymethoxy)calix[4]resorcinarene, 5,11,17,23,29,35‐hexamethyl‐37,38,39,40,41,42‐hexakis(carboxymethoxy)calix[6]arene, and 5,11,17,23,29,35,41,47‐octa‐tert‐butyl‐49,50,51,52, 53,54,55,56‐octakis‐(carboxymethoxy)calix[8]arene, which were prepared by the reaction of C‐methylcalix[4]resorcinarene, p‐methylcalix[6]arene, and ptert‐butylcalix[8]arene, respectively. The thermal stability of the obtained calixarene derivatives containing spiro ortho ester groups was examined with thermogravimetric analysis, and it was found that these calixarene derivatives had good thermal stability. The photoinitiated cationic polymerization of spiro ortho ester groups in calixarene derivatives 3a–3c was examined with certain photoacid generators in the film state. Interestingly enough, the reaction of calixarene derivatives did not proceed with only photoirradiation; however, the reaction proceeded smoothly when the photoirradiation was followed by heating. Furthermore, calixarene 3a , composed of a C‐methylcalix[4]resorcinarene structure, showed the highest photochemical reactivity in this reaction system. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1293–1302, 2002  相似文献   

5.
A bis‐tert‐alcohol‐functionalized crown‐6‐calix[4]arene (BACCA) was designed and prepared as a multifunctional organic promoter for nucleophilic fluorinations with CsF. By formation of a CsF/BACCA complex, BACCA could release a significantly active and selective fluoride source for SN2 fluorination reactions. The origin of the promoting effects of BACCA was studied by quantum chemical methods. The role of BACCA was revealed to be separation of the metal fluoride to a large distance (>8 Å), thereby producing an essentially “free” F?. The synergistic actions of the crown‐6‐calix[4]arene subunit (whose O atoms coordinate the counter‐cation Cs+) and the terminal tert‐alcohol OH groups (forming controlled hydrogen bonds with F?) of BACCA led to tremendous efficiency in SN2 fluorination of base‐sensitive substrates.  相似文献   

6.
The crystal structures of acetonitrile solvates of two related lithium calixarene complexes have been determined by low‐temperature single‐crystal X‐ray diffraction using synchrotron radiation. Bis(μ‐5,11,17,23‐tetra‐tert‐butyl‐26,28‐dihydroxy‐25‐methoxy‐27‐oxidocalix[4]arene)dilithium(I) acetonitrile tetrasolvate, [Li2(C45H57O4)2]·4C2H3N or [p‐tert‐butylcalix[4]arene(OMe)(OH)2(OLi)]2·4MeCN, (I), crystallizes with the complex across a centre of symmetry and with four molecules of unbound acetonitrile of crystallization per complex. Tetraacetonitrilebis(μ‐5,11,17,23‐tetra‐tert‐butyl‐26,28‐dihydroxy‐25,27‐dioxidocalix[4]arene)tetralithium(I) acetonitrile octasolvate, [Li4(C44H54O4)2(C2H3N)4]·8C2H3N or {p‐tert‐butylcalix[4]arene(OH)2(OLi)[OLi(NCMe)2]}2·8MeCN, (II), also crystallizes with the complex lying across a centre of symmetry and contains eight molecules of unbound acetonitrile per complex plus four more directly bound to two of the lithium ions, two on each ion. The cores of both complexes are partially supported by O—H...O hydrogen bonds. The methoxy methyl groups in (I) prevent the binding of any more than two Li+ ions, while the corresponding two O‐atom sites in (II) bind an extra Li+ ion each, making four in total. The calixarene cone adopts an undistorted cone conformation in (I), but an elliptical one in (II).  相似文献   

7.
Two‐ and Threefold Intramolecular Brigdging p‐tert‐Butylcalix[8]arene Triphosphates – Synthesis, Structure and Stereochemistry [1] The phosphorylation of p‐tert‐butylcalix[8]arene ( 1 ) with phosphorus pentachloride and hydrolysis gives intramolecular bridging tert‐butylcalix[8]arene triphosphates. The reactivity (esterification, dehydratisation, complexation), the structure (nmr and x‐ray), and the stereochemical behaviour of the phosphates will be discussed.  相似文献   

8.
A new oligomeric calix[4]arene‐thiacrown‐4 ( 5 ) was synthesized via a condensation reaction of 5,11,17,23‐tetra‐tert‐butyl‐25,27‐bis‐(4‐aminobenzyloxy)‐calix[4]arene‐thiacrown‐4 ( 4 ) with adipoyl dichloride. In this oligomerization reaction only five/six calix[4]arene‐thiacrown‐4 units were linked in the oligomeric chain. The complexation studies of 5 were made with liquid–liquid‐ extraction and solid–liquid‐sorption procedures. For comparison, the extraction efficiencies of monomers 1 , 3 , and 4 to selected transition metals are reported. The selectivity of monomers 3 and 4 toward Cu2+, Hg2+, and Pb2+ was lost after oligomerization in the two‐phase extraction systems. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 186–193, 2004  相似文献   

9.
The best of both worlds. Amphiphilic hybrid molecules, in which water‐exposed glycodendrons are attached to a hydrophobic p‐tert‐butylcalix[4]arene scaffold, display strong affinities for both carbohydrate‐binding proteins and polystyrene surfaces (shown schematically). The molecules can form monolayers useful in bioanalytical devices.  相似文献   

10.
Theoretical calculations were performed to elucidate the ability of the recently reported bis‐tert‐alcohol‐functionalized crown‐6‐calix[4]arene (BACCA) molecule to promote nucleophilic fluorination of alkyl mesylates with cesium fluoride reagent. It was found that a similar structure, named BACCAt, can separate the cesium fluoride ion pair in tert‐butanol solution. This separation has a free energy cost, even considering the double hydrogen bonds with the fluoride ion. The solvent has an important effect on the stabilization of this complex, due to interaction with the high dipole moment of the separated ion pair. The observed rate acceleration effect involves a structure with double hydrogen bonds between the BACCAt and the centers of negative charges of the SN2 transition state. The predicted free energy barrier of 27.3 kcal mol−1 is in excellent agreement with the estimated experimental value of 26.2 kcal mol−1.  相似文献   

11.
王浩  张衡益  刘育 《中国化学》2005,23(6):740-744
Two calix[4]arene isomers with benzaldehyde moieties, i.e., 5,11,17,23-tetra-tert-butyl-25,27-bis[2-(o-formyl-phenoxy)ethoxy]-26,28-dihydroxycalix[4]arene (3) and 5,11,17,23-tetra-tert-butyl-25,27-bis[2-(p-formylphenoxy)-ethoxy]-26,28-dihydroxycalix[4]arene (4), were synthesized according to a newly designed route in high yields, and their crystal structures have been determined by X-ray crystallographic study. The photophysical behavior on complexation of calix[4]arene derivatives 3 and 4 with terbium(Ⅲ) nitrate was investigated in anhydrous acetonitrile at 25℃ by UV-Vis and fluorescence spectroscopies. The crystallographic structure of 3 indicated that the eight oxygen atoms formed a preorganized ionophoric cavity due to intramolecular π-π stacking, which could encapsulate lanthanide ions tightly. In sharp contrast, the compound 4 formed a linear array by intermolecular π-π stacking, hence the oxygen atoms of pendant arms could not coordinate with metal ions, giving a poor binding ability to Tb^3 . The absorption spectra of 3 with Tb^3 showed clearly a new broad intense absorption at 385nm. Interestingly, the narrow emission line spectrum has also been observed for compound 3 with Tb^3 , and the results obtained were discussed from the viewpoint of energy transfer mechanism between host structures and the properties of lanthanide ions.  相似文献   

12.
We first make use of aminolysis of calix[4]arene esters to synthesize calix[4]arene amides. When the two ethyl esters of the calix[4]arene esters are aminolysized, the 1, 3-amide derivative is formed selectively. The crystal structures of the calix-[4]arene with two butyl amide (3b) and four butyl amide moieties (4b) were determined. The intermolecular hydrogen bonds make 4b form two-dimensional net work insolid state. The 1H NMR spectra prove that 3b is of a pinched cone conformation, while 4b and tetraheptylamide-calix[4]arene (6b) take fast interconversion between two C2v isomers in solution and appear an apparent cone conformation at room temperature. As decreasing temperature, the interconversion rate decreases gradually and, finally, the interconversion process is frozen at Tc = -10℃, which makes both conformations of 4b and 6b the pinched cone structures. The hydrogen bond improves the interconversion barrier, and the large different values of the potential barrier between 6b and 4b (or 6b) may  相似文献   

13.
The synthesis of two new flavin substituted calix[4]arene derivatives, 9 and 10 , is described. The first flavin substituted calix[4]arene derivative 9 was synthesized by the reaction of 3‐methylalloxazine ( 5 ) with 25,27‐bis(3‐bromopropoxy)‐26,28‐dihydroxy‐5,11,17,23‐tetra(tert‐butyl)calix[4]arene ( 4 ) in high yield (92%). The other derivative 10 was prepared from 3‐methylalloxazine‐1‐acetic acid ( 7 ) and 25,27‐bis(3‐cyanopropoxy)calix[4]arene ( 3 ). All new compounds were characterized by a combination of FT‐IR and 1H‐NMR spectroscopy, and elemental‐analysis techniques.  相似文献   

14.
A series of novel double‐armed p‐(tert‐butyl)calix[4]arenes, carrying benzoylamido, 4‐nitrobenzoylamido, isonicotinamido, α‐naphthamido, acetamido, propionamido, or butyramido groups (see 2 – 8 , resp.) were synthesized in 80 – 86% yield by the reaction of the lower‐rim 1,3‐bis(aminoethoxy)‐substituted calix[4]arenediol 1 with the corresponding acylating agents. Their structures were established by elemental analysis, mass, IR, UV, and 1H‐NMR spectroscopy. Ion‐selective electrodes (ISEs) for Pb2+, carrying 2 – 8 in a PVC membrane as neutral ionophore, were prepared, and their selectivity coefficients for Pb2+ (K) were determined against other heavy‐metal ions, alkali and alkaline earth metal ions, and ammonium ions by means of the separate‐solution method. The results obtained indicated that the electrodes based on the calix[4]arene‐derived amides 2 – 8 as the neutral ionophores were all Pb2+ selective and exhibited almost theoretical Nernstian slopes, except for 3 and 4 . Typically, the Pb2+‐selective electrode based on 6 – 8 exhibited almost Nernstian slopes for Pb2+ over a relatively wide concentration range and had a fast response time as well as a long lifetime, although the silver ion interfered strongly. These ISEs based on 6 – 8 showed a relatively good Pb2+ selectivity against most of the interfering cations examined, except for Ag+. The effect of the side‐arm functions of calix[4]arene derivatives 2 – 8 on the Nernstian slopes and on the selectivity coefficients for Pb2+ obtained with the Pb2+ ISEs based on 2 – 8 is discussed.  相似文献   

15.
Two new kinds of alanine‐substituted calix[4]arene stationary phases of 5,11,17,23‐p‐tert‐butyl‐25,27‐bis(l ‐alanine‐methylester‐N‐carbonyl‐methoxy)‐26,28‐dihyroxycalix[4]arene‐bonded silica gel stationary phase (BABS4) and 5, 11, 17, 23‐p‐tert‐butyl‐25,26,27,28‐tetra(l ‐alanine‐methylester‐N‐carbonyl‐methoxy)‐calix[4]arene‐bonded silica gel stationary phase (TABS4) were prepared and characterized in the present study. They were compared with each other and investigated in terms of their chromatographic performance by using polycyclic aromatic hydrocarbons, disubstituted benzene isomers, and mono‐substituted benzenes as solute probes. The results indicated that both BABS4 and TABS4 exhibited multiple interactions with analytes. In addition, the commonly used Tanaka characterization protocol for the evaluation of commercially available stationary phases was applied to evaluate the properties of these two new functionalized calixarene stationary phases. The Tanaka test results were compared with Zorbax Eclipse XDB C18 and Kromasil phenyl columns, respectively. BABS4 has stronger hydrogen‐bonding capacity and ion‐exchange capacity than TABS4, and features weaker hydrophobicity and hydrophobic selectivity. Both of them behave similarly in stereoselectivity. Both BABS4 and TABS4 are weaker than C18 and phenyl stationary phases in hydrophobicity and hydrophobic selectivity.  相似文献   

16.
A series of novel 1,3‐altemate calix[4]arene azacrowns having mono and bis crown ethers on the lower rim of the calix[4]arene framework were synthesized. Solid‐state structures confirmed the three dimensional conformation of compounds 1–3.  相似文献   

17.
郭倩玲  马淑兰  朱文祥  刘迎春  张静 《中国化学》2005,23(10):1387-1390
The X-ray crystallographic structure was reported for a dinuclear copper(Ⅱ) complex with a tetraanionic ligand of p-tert-butylsulfonylcalix[4]arene [Cu2L(CH3OH)6]·4CH3OH (H4L=p-tert-butylsuffonylcalix[4]arene). The complex belongs to triclinic system, P1^-- space group, with a = 1.2303(3) nm, b = 1.2377(3) nm, c = 1.3110(3) nm, a =66.862(4)°, β= 67.206(4)°, γ=61.711(3)°, Z= 1, V= 1.5659(7) nm^3, Dc= 1.371 g/cm^3, F(000) = 682,μ(Mo Kα) = 0.883 mm^-1, R1 =0.0325, wR2=0.0870. In this complex, the calix[4]arene acts as a bis-tridentate chelating ligand with the 1,2-alternate conformation.  相似文献   

18.
A germacalix‐crown, 25,27‐bis[1‐(3‐trimethylgermylpropyl)oxy]calix[4]arene‐crown‐6, 1,3‐alternate ( 1a ), and its carbon analog, 25,27‐bis‐[1‐(4,4‐dimethylpentyl)oxy]calix[4]arene‐crown‐6, 1,3‐alternate ( 1b ), were prepared and their structures were confirmed by elemental analysis and 1H and 13C NMR spectroscopy. A cation transport test indicated that both compounds exhibited much the same cation transport ability, so that the role of the germanium moiety in capturing and transporting counteranions is not yet clear. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

19.
Three new A,C-diamide bridged p-tert-butylcalix[6]arenes were synthesized from p-tert-butylcalix[6]arenes by bridging ClCH2CONH(CH2)nNHCOCH2Cl(n=3,4,6) in acetonitrile using K2CO3 as a base in 17%-25% yields.It was found that the bridged calix[6]arenes with shorter bridges (n=2,3,4 in N′,N′-bischloroacetodiamines) adopt cone conformation, but the last one (n=6) adopts alternate conformation, i.e., accompanying the lengthening of bridge, the conformation of A,C-bridged calix[6]arenes changes from cone to alternate.  相似文献   

20.
The reaction behaviour of 1, 3, 5‐triaza‐2σ3λ3‐phosphorin‐4, 6‐dionyloxy‐substituted calix[4]arenes towards mono‐ and binuclear rhodium and platinum complexes was investigated. Special attention was directed to structure and dynamic behaviour of the products in solution and in the solid state. Depending on the molar ratio of the reactands, the reaction of the tetrakis(triazaphosphorindionyloxy)‐substituted calix[4]arene ( 4 ) and its tert‐butyl‐derivative ( 1 ) with [(cod)RhCl]2 yielded the mono‐ and disubstituted binuclear rhodium complexes 2 , 3 , and 5 . In all cases, a C2‐symmetrical structure was proved in solution, apparently caused by a fast intramolecular exchange process between cone conformation and 1, 3‐alternating conformation. The X‐ray crystal structure determination of 5 confirmed [(calixarene)RhCl]2‐coordination through two opposite phosphorus atoms with a P ⃜P separation of 345 pm. The complex displays crystallographic inversion symmetry, and the Rh2Cl2 core is thus exactly planar. Reaction of 1 and of the bis(triazaphosphorindionyloxy)‐bis(methoxy)‐substituted tert‐butyl‐calix‐[4]arene ( 7 ) with (cod)Rh(acac) in equimolar ratio and subsequent reaction with HBF4 led to the expected cationic monorhodium complexes 5 and 8 , involving 1, 3‐alternating P‐Rh‐P‐coordination. The cone conformation in solution was proved by NMR spectroscopy and characteristic values of the 1J(PRh) coupling constants in the 31P‐NMR‐spectra. Reaction of equimolar amounts of 4 with (cod)Rh(acac) or (nbd)Rh(acac) led, by substitution of the labile coordinated acetylacetonato and after addition of HBF4, to the corresponding mononuclear cationic complexes 9 and 10 . Only two of the four phosphorus atoms in 9 and 10 are coordinated to the central metal atom. Displacement of either cycloocta‐1, 5‐diene or norbornadiene was not observed. For both compounds, the cone conformation was proved by NMR spectroscopy. Reaction of 4 with (cod)PtCl2 led to the PtCl2‐complex ( 11 ). As for all compounds mentioned above, only two phosphorus atoms of the ligand coordinate to platinum, while two phosphorus atoms remain uncoordinated (proved by δ31P and characteristic values of 1J(PPt)). NMR‐spectroscopic evidence was found for the existence of the cone conformation in the cis‐configuration of 11 .  相似文献   

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